With the move to replacement metal gate (RMG) technologies, the traditional polysilicon resistor has become difficult and expensive to integrate with semiconductor devices and even more difficult to achieve precision resistor requirements. One solution is to integrate into a middle-of-the-line (MOL) process a thin film metal resistor contacted by a source/drain contact (CA) or a gate contact (CB) using a metal deposition, lithography, and etch process. However, the integration of a thin film metal resistor can be a challenge due to the tight tungsten (W) CA/CB chemical mechanical polishing (CMP) margin and the impacts of CMP on the thin film metal resistor.
A need therefore exists for methodology for integrating a sandwich damascene resistor in MOL processes, and the resulting product.